1. Field of the Disclosure
The present disclosure relates to a power amplification module.
2. Description of the Related Art
A power amplification module is used in a mobile communication device such as a cellular phone in order to amplify the power of a signal to be transmitted to a base station. In such a power amplification module, the gain may be switched in accordance with the output level in order to improve the power addition efficiency. In the power amplification circuit disclosed in Japanese Unexamined Patent Application Publication No. 2002-151982 for example, the gain of the power amplification circuit is adjusted by controlling the bias in accordance with the output level.
Although the gain can be adjusted by controlling the bias, the width of the adjustable range is limited. In recent years, it has been demanded that the gain be further reduced at the time of a low power output mode in power amplification modules that operate in a high power output mode or a low power output mode, and it is difficult to realize such a reduction by controlling only the bias. In addition, a configuration has been considered in which a low power output mode amplification circuit and a high power output mode amplification circuit are provided separately from each other and the signal paths are switched between using a switch in accordance with the power output mode, but the characteristics are degraded by the presence of such a switch along the signal paths.